基本的に、スクリプト API を介してスクリプト環境と Java の間でデータを渡すことができます。例えば、
final ScriptEngineManager factory = new ScriptEngineManager();
final ScriptEngine engine = factory.getEngineByName("JavaScript");
engine.eval("greeting='Hello'");
// Returning data from scripting environment to Java.
// The data can also be returned from a function
final String greeting = (String) engine.eval("greeting");
System.out.println(greeting); //prints Hello
//Passing data to scripting environment from Java
engine.put("who", "foo");
final String greetingFoo = (String) engine.eval("greeting + ', ' + who");
System.out.println(greetingFoo); //prints Hello, foo